The objectives of these studies are to examine the mechanism by which insulin activates glycogen synthetase and acetyl CoA carboxylase and to define a unified theory of insulin action. We have demonstrated that insulin mediated K ion uptake is an early obligatory step in the sequence of events leading to glycogen synthetase activation. Currently, we are studying the relationship among K ion uptake, ATPase activation, and all the biochemical reactions which are affected by insulin treatment. Regulatory mechanisms for acetyl CoA carboxylase is being studied on the basis of the existence of two forms of the enzyme. Both the phosphorylated and dephosphorylated enzyme are studied kinetically and enzymologically to relate the regulatory mechanisms associated with citrate activation of the enzyme to that of insulin activation; dephosphorylation.